Loosefill packing materials are well known to those skilled in the art. By way of illustration and not limitation, loosefill packaging materials made from expanded starch products are described in U.S. Pat. Nos. 5,512,090, 5,252,271, 4,863,655, 5,035,930, 5,043,196, and the like. The disclosure of each of these United States patents is hereby incorporated by reference into this specification.
U.S. Pat. No. 5,512,090 of Hans G. Franke is typical of the prior art patents describing loosefill packaging material. The loosefill packaging material of this patent contains from about 3 to about 10 percent of proteinaceous grain meal such as, e.g., white cornmeal; the presence of this proteinaceous grain meal makes the loosefill material attractive to rodents and insects, and it imparts an odor to the loosefill material which is especially noticeable in warmer climates.
The preferred embodiment of the Franke patent is described in the Example thereof. According to the patent, the density of the product was 0.54 pounds per cubic foot, which was allegedly substantially superior to the densities of the competitive "ECO-FOAM" material (with a density of 0.60 pounds per square foot) and "ENVIROFIL" material (with a density of 0.64 pounds per cubic foot). This density, however, is unacceptably high.
It is an object of this invention to provide a novel loosefill material with a density of from about 0.33 to about 0.44 pounds per cubic foot.
It is another object of this invention to provide a substantially odor-free loosefill material.
It is yet another object of this invention to provide a novel loosefill material with a uniform cell structure.
These and other objects will be apparent from the following description of the invention.